"Skype Education: Shark Science in Action" by Jillian Morris

Skype is changing the way the world learns, and educators can now tap into formerly unreachable subjects to open up their classrooms and students’ minds. My name is Jillian Morris, and I am the founder of Sharks4Kids, a US-based nonprofit that uses this technology to expand our youth’s investment in shark science and conservation. We offer a variety of shark lessons via Skype as part of our education outreach program, but after chatting with Sharklab director (Dr. Tristan Guttridge) and media manger (Chris Lang), we decided to take our lessons to a whole new level.

What about bringing the classroom to the field? About one month ago, we began discussing the idea of doing a LIVE shark ‘work-up’ in the lab for students to watch from their hometown. With an all-star education team at hand, we divvied up responsibilities and rehearsed a few “dry” runs (literally) to set aside needed equipment, work out any stage fright kinks, determine ideal camera angles, and test the technical connection of this endeavor. Yes, a shampoo bottle did fill in for a live shark at these times. Without any mountable webcams, a bulky laptop would have to suffice. We also knew fingers would need be crossed to will Bimini’s often dodgy internet to run smoothly for our first live test sessions. Now we just needed a couple of classes to be our guinea pigs. 

I immediately contacted my mom, who teaches 6th grade science in Maine, to see if her students would want to see a live shark work up. The answer was of course, yes. I then asked one of my favorite teachers, one whose classroom I have visited via Skype and in person, Mr. Joe Grabowski. Joe teaches 8^th grade students in landlocked Guelph, Ontario and his response was, “I’d like to think by now you know me well enough to know my answer!” There. We had our first two gigs booked.

Our team of four gathered at the lab on game day. Chris and assistant manager, Lorna Scribner, putted out to the semi captive pens just outside to transport a nurse shark, while volunteer Molly Austin and I prepped and spruced up the lab. We brought and filled a large blue tub inside with saltwater, then set a bilge pump within to keep the water moving and well-oxygenated. Nurse sharks are very hardy, so their transport and placement into a temporary aquarium is perfectly safe. 

At birth, nurses are approximately 28 cm and are covered head to tail with dark spots, making them adorable ambassadors for sharks in general. Our Skype star measured 42 cm in length, so we estimated it to be about a month old. We all spend A LOT of time with sharks, but it always makes me happy to see people’s excitement over nurses given how common they are around Bimini. Everyone at the Shark Lab was taking pictures and commenting on the cuteness of the “chocolate chip cookie,” and we were genuinely eager to show the shark to the students.  With our baby nurse settled in the holding pen, we made the final adjustments in preparation for the talks. 

The first call came in from my mom’s class of 6^th graders, and although they could see us clearly, all we could make out on our screen end were glowing shapes of green. We decided to go with it, anyway. I made the introduction, explaining where we were, when and why the lab was created, adding a bit about the Bahamas’ shark sanctuary. Molly then discussed the semi captive routine at the lab, describing how we find the sharks locally, our feeding methods, and their typical monthlong duration in the holding pens for research and education. Chris then jumped in to explain the shark’s anatomy, from locating sensory organs to determining the sex. We had a baby boy! Because nurses don’t have that typical, jaws-inspired look most people envision when they picture a shark, they are ideal for demonstrating how diverse the size, shape, and color of sharks can be. The kids were now ready to see the ‘work-up’..!

Lorna talked the students through this process, which is our simple way of saying ‘collecting and measuring data on a shark.’ Lorna took the pre-caudal and total length measurements, explaining that we do not take a fork length for nurse sharks because they do not have the bottom lobe of the caudal fin (tail). She scanned the shark for a PIT tag, asking the students if they had a cat or dog implanted with a similar microchip at home. Making connections to familiar concepts helps create a stronger understanding for the students. DNA and isotope samples were not taken, but the process and reason for collection was explained. To complete the work-up, Lorna inserted an orange color tag into the first dorsal fin of the shark. These tags are used for visual identification of specific sharks without having to actually recapture them. 

We concluded the session with a Q&A, and many kids were interested in learning about other shark species found in Bimini, especially those that the lab researched. Although doing the entire talk with a laptop was not the easiest (my arms were shaking a bit from holding it stable close to the shark!), we made it work!

Joe’s class joined us for round two, and we made a few adjustments like altering the camera angle and adding a plastic bag over the keyboard. Chris bravely held his laptop over the holding bin to zoom in on body parts like ampullae and nasal barbels. We lost connection briefly, but were quickly up and running. The students wanted to know the smallest and largest sharks ever tagged by the lab (our star was in the running for the former). They even asked if we had ever seen or tagged a great white or basking shark off Bimini; DREAM COME TRUE FOR ALL OF US if this were to happen. 

Watching this idea take form in reality further solidified the notion that a bit of will power, flexibility, and experimentation can go a long way. We are all really excited to connect with more classrooms, as it was a blast through and through from brainstorming discussions to rehearsing, and most of all, giving the final delivery. Providing kids with facts and a glimpse into the real world of shark science via Skype is not only powerful, but also really fun. Big thanks to Mrs. Morris and Mr. Grabowski for welcoming us into your classroom! Hopefully there are now some eager future marine biologists in the making! Please email Sharks4Kids (Sharks4Kids@gmail.com) or the Bimini Sharklab (opportunities@biminisharklab.com) to book a Skype date of your own.

Jillian Morris

Founder of Sharks4Kids

Website: www.sharks4kids.com

Facebook: Sharks4Kids 

Twitter: @BiminiSharkGirl & @Sharks4Kids 

"My Secret Babies" by Annie Anderson

In this blog, I'd like to share a not-so-well-kept secret, an ongoing rendezvous, which started with myself and five newborn lemon sharks back in Bimini, Bahamas June 2013.

One blistering hot day in Bimini I had time to kill, so I decided to grab my cap, shades, and GoPro and head towards the shallows just off the beach in search of some critters.

It's a beautiful walk with submerged mangrove roots reaching for the surface at low tide, crabs darting about their holes and an abundance of fish illuminated by the bright, white sandy bottom. Heaven! These 'flats' as they're known are also home to big schools of bonefish, stingrays, sharks, and even the odd barracuda on the look-out for an easy meal.

During my walk that day, I was fortunate enough to spot a huge school of bonefish only 3 or 4 meters from the shore. So, I tiptoed out and placed my GoPro under the water to see what I could capture. Enjoying the view, I stood captivated by the camouflaged, almost transparent school of fish that swayed in and out of visibility. Well, that was until my peripheral vision noticed a darker, more distinctive shadow tailing the school. It was a juvenile lemon shark, which was approximately 60 cm, so most likely a newborn, probably born within the last few weeks! We all shared a beautiful moment in this ankle-deep, 50 cm tide of water.

Now bonefish are a fair size (roughly 30-50 cm) so I was confused by the shark’s behaviour, as it was highly unlikely the shark could capture one of these guys even if it wanted to!  But then, I spotted another lemon. And another. There were five in total, all within 10-15 meters of each other, and after no time at all, they were swimming around my ankles like I didn't exist. Maybe these sharks were so young that they were simply seeking protection within the bonefish school? Were they playing the safety in numbers card? Or were they simply being social? (Link to Dr Tristan Guttridge's lemon shark social behaviour paper: http://www.int-res.com/abstracts/meps/v423/p235-245/).

My GoPro was fixed in the shallows as the lemons appeared unfazed by its presence; if anything they were interested in it and nosed it on a number of occasions! I spent hours with them, and as the tide fell further they all slowly disappeared...

The next day, I strolled out to the same spot to find 'my babies' (now affectionately named) promptly patrolling the shallows, waiting for me, or so I liked to believe! With each day, I continued to visit them, observing their wild social behaviour and keeping my little secrets close to heart. Within the week they reduced to 4. I searched everywhere for the missing pup but as these babies have a small, rather limited home range (they don't venture too far), I came to the conclusion the barracuda’s patience paid off.

So one afternoon I uploaded my GoPro pictures to my laptop and decided to share ‘my babies’ with the Sharklab. The lab has conducted research on Bimini’s juvenile lemon sharks for over 20 years, venturing into distant channels and nursery grounds as far as the tip of the north island. Upon learning my secret (baby sharks refuging less than 100 meters from their backyard beach), they decided to catch these pups to measure, weigh, and tag them all before releasing them back into their familiar waters. It was hard seeing 'my babies' captured as I felt a special connection with them, but ultimately I know the data that these guys contribute towards shark research could go on to protect them, their buddies, their extended family and even their home, the all-important mangrove rich nursery grounds. This year, it was proven female lemon sharks here in Bimini return to the exact same place THEY were born to give birth themselves. I don't mean country, I mean the EXACT same mangrove nursery! How cool is that (Paper link: http://onlinelibrary.wiley.com/doi/10.1111/mec.12583/abstract)! It had been a long waiting game to prove this fact, as lemons mature late (approximately 13 years for females) and give birth to only 10-20 pups every other year. Keep in mind, science requires much more than one example of this birthing behaviour (multiple females) to have a basis for credibility.

This research also contributes and strengthens arguments to protect worldwide nursery grounds as it demonstrates how important these 'playgrounds' really are for pupping sharks and much more. Some mangroves, including those here in Bimini face being destroyed by us humans for the likes of building developments or hotels. I shared my babies for the bigger picture.

Maybe, one day ‘my female babies’ will survive and come back to these shallows to pup for themselves. I like to think so.

After weeks had passed, one day in late June I visited my usual spot to disappointedly find out that my lemon count had reduced to three. Nature’s 'survival of the fittest' motto had taken its toll. Since that visit, I walked out to my spot a number of times, relieved to see my three babies still remaining.

After a holiday to the UK, I returned to Bimini in May 2014 with my 8 week old baby and immediately took her out to the flats in search of my lemons. A year on from my first sighting and all 3 were still there, swimming around each other, in the same location just as they were when I left! Such a wonderful sight to return home to...

Just a few days after our return, I decided to walk back out and what did I find?? Another batch of babies!! I counted 5 newbies, plus my original 3! So my little lemons have some new friends (maybe cousins!)! Although research suggests that Bimini lemons hang out with sharks of a similar size (even through to adulthood), I like to think my babies are open-minded and would accept the slightly smaller newbies. :-)

I wonder if the mum of the original babies will come back next year to pup again, giving the existing lemons some brothers and sisters? Their DNA will reveal all. :-)

Well, that's it for now...I hope you enjoyed my (not so much of a) secret. I'll be sure to keep you all updated with how my 8 babies are doing! 

Annie Anderson

Founder of SharksNeedLove, Resident of South Bimini, Fiancé of Lab Director (Dr. Tristan Guttridge), Mother of Isla Guttridge
Facebook: Sharks Need Love
Twitter: @SharksNeedLove
Instagram: @SharksNeedLove

Follow the Food: Reading the Diary of Lemon Shark Movements and Behavior (9/1/2014)

 Accelerometry, Active Tracking, and Prey Abundance Surveys 

Photo of Rob and volunteers deploying a 109 cm lemon shark with 'tag package'

Lab PI Rob Bullock studies lemon shark behavior and habitat use here in Bimini. We attach tag packages (acoustic transmitter-bound accelerometers) on the dorsal fins of sharks to learn more about where they go and how they spend their days. The acoustic transmitters allow us to actively and passively track the sharks to determine locations, and the accelerometers record fine-scale movements in three dimensions (x, y, z), which we translate into behavior. A small sensor in this device deviates from the center with increasing amplitude as the shark accelerates, logging even the subtlest of movements. Presuming we recapture the tagged individuals after releasing them into the wild, we download this data so we can learn more about what these sharks do on a day and night basis.

 

Photo of two mojarra skulls in lemon shark stomach contents (left), and lemon shark trailed by mojarra (right), both taken by Chris Lang

Lemon sharks have eviscerable stomachs, which, as unusual as this may sound, we have used for our advantage to determine their preferred and predominant diet. Yes, we have inserted forceps into the mouths of anesthetized sharks to evert their stomachs and proceed with the analysis. A study back in 2010 by former Sharklabber, Stephen Newman, found out that despite the wide abundance of juvenile and adult grunts, mangrove snappers, barracuda, needlefish, and parrotfish that live within the local lemon shark refuge, more than 50% of a juvenile lemon’s diet is made up of the Yellowfin mojarra (Gerres cinereus) by weight and percentage index of relative importance. Given this undeniable preference, we felt it obligatory to assess the prey distributions for our little ones.

Still-shot of BRUVS recording near mangroves, note the abundance of snappers and lurking lemons in the background

To supplement his project, Rob has supervised two Master’s students to deploy BRUVS, apparatuses used to monitor the abundance of marine biodiversity, in the lagoon. Baited Remote Underwater Video Stations (BRUVS) are GoPro-mounted frames made of rebar that survey the proximate and passing species. Overall, more than 125 BRUVS were deployed. Rob and his students, Henrietta and George, placed these frames in a variety of sub habitats (sandy flats, sea grass beds, mangrove fringes) within, around, and beyond the known lemon shark nurseries. It took a lab-wide effort to watch every video and record the number of passing individuals for each species, which we used to extrapolate their population abundances in the lagoon. 

Slide photograph of North Bimini Marine Reserve's assessed faunal distribution taken from Rob Bullock's AES presentation

Here (above) is the summary of their findings. We divvied up the fish into their respective families, read top-down from left to right: mojarra, snapper, jack, needlefish, grunt, and parrotfish. The location of each circle represents a BRUVS deployment, and each diameter corresponds to the abundance determined from the video assessments (bigger circle-->more fish of this species found). It’s worth mentioning the apparent increase in diversity AND abundance near the mangrove-fringed land, marked by green. We hope developers on the islands look at this BRUVS study to understand exactly what is at stake when they decide to cut down these trees to build a house, or even a golf course...

Photo of 'tag package' comprised of acoustic transmitter (top) and accelerometer, taken by Chris Lang 

The focal point of Rob’s research, however, comes from tracking and accelerometry. Rob has to locate and net lemon sharks of a particular size range, and then tag them with the fused instruments (above). These function separately, but ultimately provide us with invaluable data, allowing us to record both the generic locations and fine scale movements of the sharks.

Photo of Matt Larsen (a Sharklab volunteer) actively tracking lemons outside the nursery entrance with hydrophone in hand

With receivers set up inside and around the lagoon, along with hydrophone-wielding trackers (above), we can both passively and actively track these sharks. Sonotronic Receivers are strategically deployed in these areas, and they pick up low frequency pulses emitted by the acoustic transmitter within a small range (~300 m). This is called passive tracking. These two methods complement one another to inform us on where they are going throughout the desired duration. 

Photo of Brianna Hall (Sharklab Volunteer) performing ethogram and observing accelerometer-tagged shark behavior from watchtower, taken by Chris Lang'

But what role do the accelerometers play in this? The aforementioned results are only based off data taken from acoustic transmitters. Accelerometers measure something very different. Interpreting the data from one of these is like translating a language written in seismic wave magnitudes into a shark’s behavior. Saying this is difficult is an understatement. 

Rob and our volunteers perform an ‘ethogram’ to observe a tagged shark in captivity, scribing its actions under various simulated circumstances (chasing prey, avoiding predation, resting, shaking head to ease consumption) with their respective times, and then interpreting these results using the behavior key he just created. 

Results of tagged lemon shark movements in relation to fish abundance in North Bimini Marine Reserve, taken from Rob Bullock's AES presentation

From Rob’s 12 tagged sharks so far, results suggest that juvenile lemons are indeed following the food, so to speak. As the water depth drops with every low tide, juvenile lemons are pushed outside the nursery and into lagoon areas that were once inhabited by larger sharks. This picture shows the logged locations from three of Rob's tagged sharks during low tide, whose paths are color-coded for viewer convenience. These findings overlap seamlessly with our BRUVS-determined abundances for juvenile lemon preferred prey species, the Yellowfin mojarra and grunts.

Example of z-axis data recording lemon shark tailbeats, the red box is a prey capture

This 12 second clip is 1/36000th of the data Rob analyzes using software for the deployment of just one shark's accelerometer. The z-axis measures the amplitude of each tailbeat from the shark. 

Every time a shark successfully captures prey, it proceeds to pump its caudal fin in speedy rhythm while shaking its head back and forth. This creates a unique output that can be seen through the high frequency, high amplitude waves as shown on the z-axis recordings within the red box above. The final set of tailbeats, shown here, are only applicable to sharks that have successfully seized prey. Across the first 12 tagged sharks, Rob has observed 84 total prey handling events, which averages out to be roughly ~1.4 successful prey captures per shark per day.

When the sharks aren’t foraging, they are resting, and he estimates this to make up about 10-20% of the lemon's daily time. To put in Rob’s words, “lemon sharks live on an energetic knife-edge,” requiring a sensitive caloric intake to sustain their metabolic requirements. 

Photo of lemon shark lining snapper and mojarra-filled mangrove roots, taken by CJ Crooks

Mangroves are essential nursery grounds for so many of the local species in Bimini, as evident from our BRUVS deployment results.  Many migratory fish we find in adulthood develop in this protected area, such as the barracuda, which can move to nearby coral reefs later on. Mangrove roots quell water turbulence and provide a settlement ground for free-swimming larvae of countless lifeforms to populate. Humans in Bimini sustain themselves primarily on sealife, and all of it is dependent on the health of the mangrove ecosystem. This interrelatedness must be addressed and thought through. 

The best tool for conservation is understanding. Observing juvenile lemon shark behavior and understanding that their foraging patterns mirror their prey distribution, we can make more informed decisions when determining areas to protect. Our lemons follow the food. But what happens when the habitat for their food source is removed? Because the status of the North Bimini Marine Reserve is still under dispute for development, we believe these results speak for themselves as to why the mangroves must stay rooted in.

Help us preserve the North Bimini Marine Reserve by signing this petition!